Wind power is considered one of the cleanest, most environmentally friendly energy sources presently available, and wind turbines have gained increased attention in this regard. A modern wind turbine typically includes a tower, a generator, a gearbox, a nacelle, and one or more rotor blades. The rotor blades capture kinetic energy of wind using known foil principles. The rotor blades transmit the kinetic energy in the form of rotational energy so as to turn a shaft coupling the rotor blades to a gearbox, or if a gearbox is not used, directly to the generator. The generator then converts the mechanical energy to electrical energy that may be deployed to a utility grid.
In many cases, accessory components are attached to the rotor blades of wind turbines to perform various functions during operation of the wind turbine. For example, it is known to change the aerodynamic characteristics of wind turbine rotor blades by adding protrusions or other structures to the surface of the blade in order to increase the energy conversion efficiency during normal operation of the wind turbine by increasing the lift force of the blades while decreasing the drag force. Such components include, for example, winglets, tip extensions, and vortex generators. The purposes and operational principals of these devices are well understood by those skilled in the art.
The installation techniques and systems for attaching conventional add-on components can be expensive and time consuming, particularly for field installations. For example, typical field installation techniques require the use of attachment fixtures and significant dwell time for curing the attachment adhesives. Further, especially for the addition of tip extensions, a prevalent conventional method involves cutting off the existing blade tip so as to integrate the extension with the internal blade structure. Such processes can be time consuming, expensive, and may damage the main blade structure. Moreover, such processes may compromise the structural integrity and/or durability of the rotor blade, as well as its aerodynamic performance. Further, certain tip extensions may increase noise in surrounding areas above acceptable limits.
In addition, wind turbines are prone to lightning strikes and, in this regard, it is a common practice to provide the turbine blades with lightning receptors spaced along the longitudinal length of the blade so as to capture and conduct lightning strikes to ground. As such, additional challenges associated with installing tip extensions onto existing rotor blades may include retaining lightning protection system functionality thereof.
Thus, the industry is continuously seeking improved methods for installing tip extensions for wind turbine rotor blades that tie into existing lightning protection systems thereof.